In the 1990s, the data industry mushroomed. Vast computer systems quietly gathered staggering amounts of personal information about virtually every American adult, mostly for business and marketing purposes. After the 9/11 attacks, national security officials reached out to data companies for help in finding potential terrorists. Now, there may be No Place to Hide.

In 1975, Senator Frank Church headed a congressional commission that investigated widespread abuses by U.S. intelligence and law enforcement agencies. Church warned about the government's power to turn surveillance technologies on its own citizens if it chose to.

In fact, Senator Church couldn't have imagined the power of information and surveillance technologies available to the government three decades later. And he wouldn't live to see how aggressively government would embrace such tools in a time of fear about national security - tools to watch and assess American citizens, all of us, in order to protect us.

In the 1960s and 70s, the FBI, under J. Edgar Hoover, spied on thousands of Americans whose politics were considered suspect. It worked actively to disrupt not only violent, radical organizations, but also law-abiding, civil rights and anti-war groups. Driven by crime-fighting and anti-communist zeal, Hoover's orders violated the Constitution and the expectation of law-abiding citizens to be left alone.

There's wide agreement that after 9/11, the government needed to do a better job of identifying threats on American soil through the use of information technology. But since these technologies, in effect, monitor almost everyone, some people worry about the potential for new abuses.

Since the 9/11 terror attacks, Americans have heard a stream of reports about new, eye-popping security technologies - tools to rate every airline passenger as a terrorism risk, or to sift through personal data about adults across the country and beyond. How far should the nation go in using your personal information for crime fighting and national security? In this new world, what are the rules?